A briefing given to an influential Pentagon advisory board is reported to have described Saudi Arabia as an enemy of the United States because of its alleged support for terrorism.

The board was told Saudi Arabia encouraged and financed extremism

According to the Washington Post newspaper, the briefing reflects a view that is gaining ground within the Bush administration.

The advisory board brings together some heavy-weight former officials, including Henry Kissinger, James Schlesinger and Newt Gingrich - and is chaired by Richard Perle, a leading advocate of a US military attack on Iraq.

The paper says the board was briefed last month by a researcher from the Rand Corporation, an influential think-tank, who argued that Saudi Arabia is so deeply implicated in terrorism that it should be considered an enemy, not an ally.

'New conservatives'

By itself, a briefing to an advisory body would scarcely matter.

The Saudis are well aware of the debate that is under way and are engaged in an expensive public relations campaign designed to recover lost ground

But the briefing reflects the views of the "neo-cons" - the new conservatives - whose views are shared by some important figures in the Bush administration.

They argue the US has for too long been over-indulgent towards Arab allies - first and foremost, the Saudis - who have encouraged and financed Islamic extremism.

If America attacks Iraq, they say, and installs a new regime there, all this will change.

Unreliable allies will have to put their house in order, or else lose US support.

Saudi anxieties

As for Saudi oil, the neo-cons argue there is plenty of oil elsewhere.

Officially, US policy remains unchanged.

But the Saudis are well aware of the debate that is under way and are engaged in an expensive public relations campaign designed to recover lost ground.

This latest report will heighten their anxieties.

More broadly, if the neo-cons were to win the argument, it would represent a revolution in American foreign policy, and one with far-reaching consequences for international affairs.